Field of the Invention
This invention relates to an improved adjustable support platform for support of a computer keyboard, the support being fully adjustable in height for individuals of varying sizes, either right-handed or left-handed, the support having a preset angle with respect to a horizontal plane to ensure support at a neutral wrist angle and a neutral finger angle position.
The advent of the personal computer in the early 1980's resulted in a total revamping and change in the office environment. Data processing and word processing could now be accomplished at much greater speeds and efficiencies. The keyboard developed for use with personal computers evolved from the technology associated with manual typewriters which required a posture suited to a slower typing rate and heavy downward stroke on the keys. Further, the manual machines and even the later generation electric typewriters provided for frequent rest periods for the operator. Fingers could rest on the keys without causing them to actuate and rests were further provided by interruptions, such as carriage returns, paper changes and manual error corrections. These short rests or mini breaks allow time for recovery from any fatigue, trauma or tension of the lower arms, wrist and fingers.
With the advent of the personal computer, office place injuries in the form of carpal tunnel syndrome have more than doubled. This trauma occurs when the nerve and tissues in the carpal tunnel within the wrist are compressed by the bones and ligaments. It results in numbness, tingling and pain in the hand and fingers that migrates to the elbow and shoulders. Corrective surgery to correct this malady is required in over 50% of the cases and in some instances, must be repeated a second time within 18 months. One culprit identified in the rise of carpal tunnel syndrome is the computer keyboard and its positioning vis-a-vis the posture of the operator. The computer and the associated keyboard have eliminated the mini or micro breaks that the operator experienced in using manual machines or late model electric typewriters. There is no longer a carriage return. Paper changes are not required and manual error corrections are performed through further use of the keyboard. Feather-touch keys on the keyboards reduce the amount of force required to actuate the keys and mandate that the operator cannot rest their fingers on the keys. Productivity is increased dramatically as a result of the development of the personal computer. Typing speeds in the form of strokes per hour have quadrupled since all corrections and directions are now performed by keyboard functions with directions to the personal computer. However, the overall method of data entry has not significantly improved. Computer operators continue to assume the traditional typing position in which the wrists are flexed. This position is acceptable for manual typewriters where the mini breaks occur in the data entry process, but is not suitable for utilizing computer keyboards for data entry where the speed of data entry has been greatly increased.
There have been many attempts to develop a keyboard support which would combine several advantages for the keyboard operator. These developments include mounts which allow the keyboard support to be slipped under the desktop, supports which allow the raising and lowering of the keyboard, and in some instances, attempts have been made to provide for the tilting of the keyboard. Examples of these developments can be found in the following U.S. Pat. Nos. 5,037,054; 5,040,760; 5,031,867; 4,988,066; 4,913,390; 4,826,123; 4,776,284; 4,706,919; 4,691,888; 4,635,893; and 4,616,798. None of the above patents address the key issues with respect to the positional relationship of the keyboard in both horizontal and vertical planes through the relationship of the positioning of the operator's forearms, wrists and fingers.
The present inventor has appreciated the advantages of an ergonomically-designed support for the keyboard and other related computer aids including document holders in which the position of the operator's forearms, wrists and fingers are maintained in a neutral position with the keyboard support in a slightly tilted, non-horizontal plane, the rear of the keyboard being slightly lower than the front of the keyboard thereby eliminating any flexation or extension of the forearms, wrists and fingers of the operator.
The present inventor has also improved the keyboard support assembly to preset the angle of the palm rest and to preset the angle of the keyboard tray to cover a wide range of anthropometric hand and finger sizes to ensure that the angle of the palm rest and keyboard tray remain in a neutral position vis-a-vis the operator. Active height adjustment would be available to accommodate the physical parameters of the individual using the keyboard and an active fine adjustment mechanism would be available to accommodate extreme variations and diversities in the anthropometric range.
The ability to preset the angle of the palm rest and keyboard tray, yet allow height adjustment and fine adjustment of this angle is accomplished through a novel adjustment means cooperative between the keyboard tray and the support means securing the keyboard tray to the desk or computer stand.